In order to activate the contract, both parties need to sign the contract. There are two scenarios for contractors.
My client has created a contract and sent it to me
In this case, you will receive an email invitation to sign the contract. Click on the Review & Sign button on the email- the contract link is embedded and leads directly to it. You will not see the unsigned contract on your dashboard, you need to access it from the email. Alternatively, your client could have sent you the direct link which should take you to the contract page.
Here's how to sign the contract
I created the contract- what's next?
After you created the contract, you will need to send it to your client for signature. Once the client has signed, you will be able to sign it as well. Just enter your client's email and add a message. They will receive the email notification.
If your client is based in the United States, you will be asked to fill in some information for the Forms W-9 (if you are a US taxpayer) or W-8BEN(E) (if you are a non-US taxpayer). These forms are needed by your client and it does not mean you will be paying additional taxes in the US (in case of W-8BEN Form).
Here are some articles that can help you with filling in US tax forms: